UV tiv thaiv qhov tseem ceeb (UPF) yog siv los ua qhov ntsuas ntsuas rau kev tiv thaiv UV ntawm textiles. Nws sawv cev rau qhov sib piv ntawm qhov nruab nrab UV hluav taws xob cov txiaj ntsig suav thaum daim tawv nqaij tsis muaj kev tiv thaiv rau qhov nruab nrab UV hluav taws xob cuam tshuam los ntawm kev suav thaum daim tawv nqaij tiv thaiv los ntawm cov ntaub.
GB/T18830–2009, "Kev Ntsuam Xyuas ntawm UV Tiv Thaiv Kev Ua Haujlwm ntawm Textiles," qhia txog cov qauv kev sim, kev qhia, kev tshuaj xyuas, thiab kev sau npe ntawm UV tiv thaiv kev ua haujlwm ntawm textiles. Lub hauv paus ntsiab lus ntawm kev xeem muaj xws li irradiating tus qauv nrog monochromatic los yog multi- xim UV rays, sau tag nrho cov spectral transmittance t(λ), thiab xam tus nqi UPF. Parallel beams yuav siv tau los irradiate tus qauv, nrog ib tug integrating kheej kheej sau tag nrho cov kis tau tus mob; Tsis tas li ntawd, lub teeb hemisphere tuaj yeem siv los irradiate cov qauv, khaws cov teeb sib txuas sib txuas. Hauv kev xyaum, qhov ntsuas ntsuas tuaj yeem ntsuas tus nqi UPF thiab t (λ) ntawm tus qauv. Thaum tus nqi UPF ntawm tus qauv yog ntau dua 50, nws tau qhia tias "UPF> 50." Raws li tus qauv no, thaum UPF ntawm ib qho qauv ntau dua 40 thiab t (UVA) av < 5%, nws tuaj yeem hu ua "UV-cov khoom tiv thaiv."
